Three decades ago, there were nine countries that fielded ballistic missiles. Today, there are 31. Several of them are unstable (Pakistan and Egypt) or unfriendly (Iran and North Korea) or both (Syria). Not coincidentally, the world has seen an increase of more than 1,200 ballistic missiles over the past five years.

Because of the nature of their regimes, North Korea and Iran are the most worrisome of the world’s missile threats. To be sure, other regimes have larger, more lethal arsenals, but those other regimes are relatively rational and stable, which means the old rules of deterrence can keep them at bay. That may not be the case with a nuclear-armed Iran or an unraveling North Korea.

Earlier this year, Beijing estimated that North Korea possesses 20 nuclear warheads – and could have 40 by 2016. Pentagon brass recently concluded that North Korea’s nuclear-capable, road-mobile KN-08 ICBM was operational. “We assess that they have the capability to reach the homeland with a nuclear weapon from a rocket,” Adm. Bill Gortney, commander of NORTHCOM and NORAD, confirmed.

Equally worrisome, North Korea tested a submarine-launched ballistic missile in May, making the missile’s range virtually irrelevant. After all, if the launch site can be moved closer to the target, even a short-range missile can strike the United States.

This is a regime, it pays to recall, that has tested nuclear weapons on several occasions and warned in 2013 it was prepared to launch “a preemptive nuclear attack” against the United States and South Korea.

In October, just weeks after signing a nuclear deal advertised as ushering in “a safer…more hopeful world,” Iran tested a medium-range missile capable of delivering a nuclear weapon – in clear violation of U.N. Security Council resolutions. Dubbed the “Emad,” the new missile is precision guided and has a range of more than 1,000 miles – enough to strike U.S. allies (and bases) in Europe, Israel, the Middle East and across the Persian Gulf.

In addition, Iran is modifying its Sajjil missile, which will extend its missile reach to 2,200 miles, bringing most of Europe within range; Iran has already demonstrated the capacity to loft a rocket into orbit, highlighting “technologies that are directly applicable to the development of ICBMs,” according to the Missile Defense Agency; and Iran has built launch sites for long-range missiles.

However, Iran’s missile reach is not limited to land-based assets. In 2004, Pentagon officials confirmed that Iran secretly test-fired a ballistic missile from a cargo ship. Hiding a Scud-type missile and launcher below decks, the ship set out to sea and then transformed into a floating launch pad, peeling back the deck and firing the missile, before reconfiguring itself into a nondescript cargo ship. As a high-level Pentagon official said at the time, “The big distinction we make between intercontinental, medium-range and shorter-range ballistic missiles doesn’t make a lot of sense if you’re going to move the missile closer to the target.”

This is a regime, it pays to recall, that normalizes terrorism into a basic government function, threatens to wipe neighboring countries off the face of the earth, invokes apocalyptic scenarios to justify its policies, and is a serial violator of international nuclear agreements.

The list is staggeringly long: In 2002, dissident groups outed Iran’s illegal nuclear-weapons program, exposing sites in Natanz and Arak. In 2003-04, international inspectors reported that Iran had breached agreements to suspend uranium-enrichment activity. In 2009, international inspectors found that Iran understated by a third its stocks of enriched uranium. Also in 2009, a secret, subterranean nuclear facility was discovered in the mountains near Qom. In 2010, the IAEA revealed evidence of attempts by the Iranian military to develop a nuclear warhead. In 2011, the IAEA concluded that Iran “carried out activities relevant to the development of a nuclear device.” When it was suspected in 2013 that Iran conducted tests for nuclear-bomb triggers in Parchin, the issue was not just papered over, but quite literallypaved over. In December 2014, U.S. agencies accused Iran of illegally acquiring components to aid in the production of weapons-grade plutonium.

The president may believe Tehran can be brought in from the cold. But the hard truth is that the Islamic Republic of Iran is a revolutionary regime committed to using intimidation, violence and terror to challenge the established global order.

Insurance

Missile defenses offer an insurance policy against the terrorist tyrannies in Iran and North Korea. “We want potential adversaries to know that not only is there a price for attacking us or our friends,” Adm. James Winnefeld, former vice chairman of the Joint Chiefs of Staff, explains, “but the attack may not succeed in the first place, resulting in pain, but no gain.”

Toward that end, the Pentagon will have 44 ground-based interceptors in Alaska and California operating by the end of 2017. In addition, the 2016 National Defense Authorization Act ordered site evaluations for a bed of ground-based interceptors on the East Coast. The Pentagon has identified possible third-site locations in Fort Drum in New York, Naval Air Station in Maine, Fort Custer Training Center in Michigan and Camp Ravenna Joint Training Center in Ohio.

The U.S. Navy now deploys 33 Aegis ballistic missile defense (BMD) warships, with plans for 48 by 2020. Wary of North Korea, Japan deploys another four, with plans for a fleet of eight Aegis BMD warships as well as a land-based variant of the system known as “Aegis Ashore.” According to a Congressional Research Service report, “Allied countries that now operate, are building or are planning to build Aegis-equipped ships include Japan, South Korea, Australia, Spain and Norway.”

In mid-2015, Japan and the United States conducted the first test flight of the SM-3 Block 2A interceptor missile, which the two Pacific allies co-developed. Japan also hosts two powerful AN/TPY-2 missile-defense radars, which are networked with other U.S. missile-defense assets, including Terminal High Altitude Area Defense (THAAD) interceptors, sea-based Aegis systems and ground-based missile interceptors in Alaska and California.

There are now five THAAD batteries activated, the newest coming online this year. Also this year, the South Korean government announced that THAAD would “significantly augment national security and defense,” but Seoul has not yet officially signed off. Washington is persistently prodding the ROK. Defense Secretary Ash Carter discussed THAAD with his counterpart in November. Deputy Secretary of Defense Robert Work recently reported, “We’re working with the government of South Korea now to determine if that is the right thing to do.” And Gen. Curtis Scaparrotti, commander of U.S. Forces Korea, has publicly recommended deployment of THAAD to South Korea. If Seoul delays too long, there are suggestions the U.S. military could quietly deploy a THAAD battery on a U.S. base in South Korea.

Israel hosts AN/TPY-2 radar systems and, with U.S. financial and technological assistance, fields concentric rings of missile defenses: from the long-range Arrow, to the medium-range David’s Sling and PAC-3, to the short-range Iron Dome. The David’s Sling system passed a series of flight tests this year and should be ready for operational deployment in 2016. The Iron Dome system intercepted 735 inbound targets and registered a kill rate of nearly 90 percent during the most recent war in and around the Palestinian territory of Gaza, Aviation Week reports. “Those 735 rockets intercepted represent dozens of Israeli casualties whose lives were saved,” an Israeli military officer observes.

The United States and the Gulf Cooperation Council – a defense alliance enfolding Saudi Arabia, Qatar, Kuwait, UAE, Bahrain and Oman – agreed in May to “a region-wide ballistic missile defense capability,” with Washington promising technical assistance. The UAE was the first foreign government to purchase a THAAD battery (in 2011). Oman was next (in 2013). And Qatar and Saudi Arabia announced plans in 2015 to purchase THAAD systems.

Turkey, land bridge connecting Europe and the Middle East, hosts an AN/TPY-2 radar. U.S. sailors have taken their posts in Romania to man a new Aegis Ashore facility. Another Aegis Ashore facility will be activated in Poland in 2018. A flotilla of four Aegis BMD warships is now based in Rota, Spain. The ships deploy to the Mediterranean, shielding NATO allies against Middle East missile threats. Germany hosts a missile-defense operations center.

“Our regional partners are vital to missile defense,” Winnefeld said earlier this year. “We couldn’t do this without them.”

Dollars and sense

Critics always latch on to the system’s misses and costs as reason to downgrade or kill missile defense. But let’s consider these criticisms.

On the issue of costs, protecting the United States from accidental launches and missile-armed madmen is not the cause of our fiscal woes. The United States has invested a total of $173.4 billion on missile defense since FY1985. In comparison to the Pentagon’s budget (about $600 billion in 2015), the size of big-ticket social programs (Medicare’s 2014 tab was $513.1 billion in 2014) or the overall federal budget (around $3.8 trillion in 2016), the amount invested in missile defense is a rounding error. Spread over 31 years, missile defense has cost $5.5 billion annually.

As to effectiveness, nothing made by man works 100 percent of the time. But it’s worth noting that in testing, this system of systems has scored successes on 69 of 86 hit-to-kill intercept attempts since 2001 – an 80-percent success rate. The Aegis sea-based system has achieved 32 successful intercepts in 39 attempts. The ground-based interceptor (which targets inbound threats near their highest point) has connected on nine of 17 intercept attempts. The THAAD system (which targets threats near the end of their flight trajectories) has scored a perfect 13 out of 13.

Critics of missile defense know that defining success as a 100-percent intercept rate makes “failure” inevitable. But if (when) a U.S. or allied city is in the crosshairs of an inbound missile, who would prefer a 0-percent chance of intercepting the killer rocket – something guaranteed by not fully funding, not testing and not deploying a missile shield – over an 80-percent or even 50-50 chance?